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REBLOZYL dosing information

Assess and review patients’ Hgb and transfusion record prior to each administration1

  • If an RBC transfusion occurred prior to dosing, use the pretransfusion Hgb for dose evaluation

REBLOZYL dose titration for response1

Dosing recommendation*
Starting dose 1 mg/kg every 3 weeks

Dose increases for insufficient response at initiation of treatment

Not RBC transfusion-free after at least 2 consecutive doses (6 weeks) at the 1 mg/kg starting dose
  • Increase the dose to
    1.33 mg/kg every 3 weeks
Not RBC transfusion-free after at least 2 consecutive doses (6 weeks) at 1.33 mg/kg
  • Increase the dose to
    1.75 mg/kg every 3 weeks
No reduction in RBC transfusion burden after at least 3 consecutive doses (9 weeks) at 1.75 mg/kg
  • Discontinue treatment

Dose modifications for predose Hgb levels or rapid Hgb rise

Predose Hgb is ≥11.5 g/dL in the absence of transfusions
  • Interrupt treatment
  • Restart when the Hgb is no more than 11 g/dL
Increase in Hgb >2 g/dL within 3 weeks in the absence of transfusions and

  • current dose is 1.75 mg/kg
  • current dose is 1.33 mg/kg
  • current dose is 1 mg/kg
  • current dose is 0.8 mg/kg
  • current dose is 0.6 mg/kg
  • Reduce dose to 1.33 mg/kg
  • Reduce dose to 1 mg/kg
  • Reduce dose to 0.8 mg/kg
  • Reduce dose to 0.6 mg/kg
  • Discontinue treatment

*Do not increase the dose if the patient is experiencing an adverse reaction.

At least 7 doses (21 weeks of treatment) unless
unacceptable toxicity occurs at any time.
At least 7 doses (21 weeks of treatment) unless
unacceptable toxicity occurs at any time.

  • Overall, 77.1% (118/153) of patients in the MEDALIST trial had their dose of REBLOZYL increased at least once2
    • 58.8% of patients (90/153) had their REBLOZYL dose increased to a maximum dose of 1.75 mg/kg

Dose increases in the event of loss of response1

  • If, upon dose reduction, the patient loses response (ie, requires a transfusion) or Hgb concentration drops by 1 g/dL or more in 3 weeks in the absence of transfusion, increase the dose by 1 dose level
  • Wait a minimum of 6 weeks between dose increases
  • Dose increases to 1.33 mg/kg and subsequently to 1.75 mg/kg may occur at any time during treatment after patients have received at least 2 consecutive doses at the prior lower dose level
  • Do not increase the dose more frequently than every 2 consecutive doses (6 weeks) or beyond the maximum dose of 1.75 mg/kg

Discontinue treatment if no reduction in transfusion burden is observed1

  • Discontinue REBLOZYL if a patient does not experience a decrease in transfusion burden after 3 doses (9 weeks of treatment) at the maximum dose level or if unacceptable toxicity occurs at any time

If a planned administration of REBLOZYL is delayed or missed, administer REBLOZYL as soon as possible and continue dosing as prescribed, with at least 3 weeks between doses1

REBLOZYL dosing modifications for adverse reactions1

Dosing recommendation*
Grade 3 or 4 hypersensitivity reactions
  • Discontinue treatment
Other Grade 3 or 4 adverse reactions
  • Interrupt treatment
  • When the adverse reaction resolves to no more than Grade 1, restart treatment at the next lower dose level
  • If the dose delay is >12 consecutive weeks, discontinue treatment

*Grade 1 is mild, Grade 2 is moderate, Grade 3 is severe, and Grade 4 is life-threatening.

Per dose reductions in chart above.

Instructions for subcutaneous administration

REBLOZYL is administered subcutaneously and is available in 2 vial sizes (25 mg and 75 mg)1

  • Prior to injection, allow solution to reach room temperature for a more comfortable injection

REBLOZYL should be reconstituted and administered by a healthcare professional1

Step 1

Verify correct dose for the patient1

  • Calculate the exact total dosing volume of 50 mg/mL solution required for the patient

Step 2

Plan and prep for injection1

  • Slowly withdraw the dosing volume of the reconstituted REBLOZYL solution from the single-dose vial(s) into a syringe
  • Divide doses requiring larger reconstituted volumes (ie, >1.2 mL) into separate similar volume injections and inject into separate sites

Step 3

Subcutaneous administration1

  • If multiple injections are required, use a new syringe and needle for each SC injection
  • Administer the SC injection into the upper arm, thigh, and/or abdomen

Subcutaneous administration.
Subcutaneous administration.

NOTE: Discard any unused portion. Do not pool unused portions from the vials.
Do not administer more than 1 dose from a vial.1

  • Do not mix with other medications

Sample calculation for SC administration of REBLOZYL1

  • Adult male aged 71 years and weighing 197 pounds (89 kg)
  • 1 mg of REBLOZYL per 1 kg = 89 mg starting dose

Total volume of reconstituted solution needed to administer 89 mg: 1.78 mL

Number of vials REBLOZYL Concentration after reconstitution Solution needed for administration Milligrams in solution
1 75 mg vial 75 mg/1.5 mL
(50 mg/mL)
Use 1.5 mL 75 mg
1 25 mg vial 25 mg/0.5 mL Use 0.28 mL 14 mg
Total volume needed 1.78 mL 89 mg

Doses with reconstituted volumes larger than 1.2 mL should be divided into separate, similar-volume syringes for injection and injected into separate sites (upper arm, thigh, and/or abdomen)

Injection 1: 0.89 mL – upper arm

Injection 2: 0.89 mL – thigh or abdomen

REBLOZYL dosing and administration video



REBLOZYL is indicated for the treatment of anemia in adult patients with beta thalassemia who require regular red blood cell (RBC) transfusions.

REBLOZYL is indicated for the treatment of anemia failing an erythropoiesis stimulating agent and requiring 2 or more red blood cell units over 8 weeks in adult patients with very low- to intermediate-risk myelodysplastic syndromes with ring sideroblasts (MDS-RS) or with myelodysplastic/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis (MDS/MPN-RS-T).

REBLOZYL is not indicated for use as a substitute for RBC transfusions in patients who require immediate correction of anemia.




In adult patients with beta thalassemia, thromboembolic events (TEE) were reported in 8/223 (3.6%) REBLOZYL-treated patients. TEEs included deep vein thrombosis, pulmonary embolus, portal vein thrombosis, and ischemic stroke. Patients with known risk factors for thromboembolism (splenectomy or concomitant use of hormone replacement therapy) may be at further increased risk of thromboembolic conditions. Consider thromboprophylaxis in patients at increased risk of TEE. Monitor patients for signs and symptoms of thromboembolic events and institute treatment promptly.


Hypertension was reported in 10.7% (61/571) of REBLOZYL-treated patients. Across clinical studies, the incidence of Grade 3 to 4 hypertension ranged from 1.8% to 8.6%. In patients with beta thalassemia with normal baseline blood pressure, 13 (6.2%) patients developed systolic blood pressure (SBP) ≥130 mm Hg and 33 (16.6%) patients developed diastolic blood pressure (DBP) ≥80 mm Hg. In adult patients with MDS with normal baseline blood pressure, 26 (29.9%) patients developed SBP ≥130 mm Hg and 23 (16.4%) patients developed DBP ≥80 mm Hg. Monitor blood pressure prior to each administration. Manage new or exacerbations of preexisting hypertension using anti-hypertensive agents.

Embryo-Fetal Toxicity

REBLOZYL may cause fetal harm when administered to a pregnant woman. REBLOZYL caused increased post-implantation loss, decreased litter size, and an increased incidence of skeletal variations in pregnant rat and rabbit studies. Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment and for at least 3 months after the final dose.



  • Serious adverse reactions occurred in 3.6% of patients on REBLOZYL. Serious adverse reactions occurring in 1% of patients included cerebrovascular accident and deep vein thrombosis. A fatal adverse reaction occurred in 1 patient treated with REBLOZYL who died due to an unconfirmed case of acute myeloid leukemia (AML)
  • Most common adverse reactions (at least 10% for REBLOZYL and 1% more than placebo) were headache (26% vs 24%), bone pain (20% vs 8%), arthralgia (19% vs 12%), fatigue (14% vs 13%), cough (14% vs 11%), abdominal pain (14% vs 12%), diarrhea (12% vs 10%) and dizziness (11% vs 5%)

Myelodysplastic Syndromes

  • Grade ≥3 (≥2%) adverse reactions included fatigue, hypertension, syncope and musculoskeletal pain. A fatal adverse reaction occurred in 5 (2.1%) patients
  • The most common (≥10%) adverse reactions included fatigue, musculoskeletal pain, dizziness, diarrhea, nausea, hypersensitivity reactions, hypertension, headache, upper respiratory tract infection, bronchitis, and urinary tract infection


It is not known whether REBLOZYL is excreted into human milk or absorbed systemically after ingestion by a nursing infant. REBLOZYL was detected in milk of lactating rats. When a drug is present in animal milk, it is likely that the drug will be present in human milk. Because many drugs are excreted in human milk, and because of the unknown effects of REBLOZYL in infants, a decision should be made whether to discontinue nursing or to discontinue treatment. Because of the potential for serious adverse reactions in the breastfed child, breastfeeding is not recommended during treatment and for 3 months after the last dose.

Please click here for full Prescribing Information for REBLOZYL.

References: 1. REBLOZYL [Prescribing Information]. Summit, NJ: Celgene Corporation; 2020. 2. Data on file. Celgene Corporation. Summit, New Jersey.